Aluminium oxide is impermeable and, unlike the oxide layers on many other metals, it adheres strongly to the parent metal. If damaged mechanically, aluminiumâs oxide layer repairs itself immediately.
Saliva helps remove oral waste and cavity-causing bacteria, protects teeth from decay by neutralizing harmful acids, and helps re-mineralize tooth enamel. Saliva also keeps oral tissues healthy by preventing infection by controlling bacteria and fungi in the mouth.
Print. The salivary glands produce saliva to moisten the mouth, to help protect teeth from decay and to digest food. The three major salivary glands are the parotid gland, submandibular gland (also called the submaxillary gland), and sublingual glands. Saliva drains into the mouth through small tubes called ducts.1  The parotid gland makes 25% of the saliva and drains into the mouth near the upper teeth.2  The submandibular gland makes 70% of the salvia and drains into the mouth from under the tongue.rint. The salivary glands produce saliva to moisten the mouth, to help protect teeth from decay and to digest food. The three major salivary glands are the parotid gland, submandibular gland (also called the submaxillary gland), and sublingual glands. Saliva drains into the mouth through small tubes called ducts.